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* Closes#5121
* [x] I have followed the instructions in the PR template
This unifies the code paths in `update_texture` somewhat, so that the
texture sampler and bind group are always replaced.
Not sure whether removing and reinserting the texture from and into the
`textures` map, or creating a new bind group, has much of a performance
impact. An alternative, as described in #5121, would be to split the
functionality for updating a texture's data from updating its options,
so that we don't have to unconditionally update the bind group (or do
something like store the options to check if they're changed).
bb9e874c83